DE102007013834B4 - Exhaust system and electrical connection system for a particulate filter - Google Patents

Abstract

Electrical connection system for a particulate filter, comprising:
a particulate filter (PF, 34) disposed in an outer shell (55), the PF (34) being segmented into a plurality of heating zones (70-74);
an outer mat (53) disposed between the particulate filter (34) and the outer shell (55);
an electrical connector (76) coupled to the outer sheath (55) of the PF (34); and
a plurality of printed interconnects (78-84) extending along the outer surface of the PF (34) from the electrical connector (76) to the plurality of heating zones (70-74),
wherein the electrical connection system comprises a plurality of pins (96) and wherein a conductive mesh material (100) is embedded and segmented in the outer mat (53) of the PF (34) to conform to the plurality of pins (96), each segment of the conductive one Mesh material (100) is surrounded by an insulating material (98).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of US Provisional Patent Application No. 60 / 786,060, filed March 24, 2006. The disclosure of the above application is incorporated herein by reference.

DECLARATION ON GOVERNMENT RIGHTS

Certain of the subject matter of the present application has been developed under contract number DE-FC-04-03AL67635, awarded by the Department of Energy. The U.S. Government has certain rights to this invention.

TERRITORY

The present disclosure relates to an electrical connection system for a particulate filter and an exhaust system comprising a particulate filter with an electrical connection.

BACKGROUND

The statements in this section merely provide background information related to the present disclosure and may not represent prior art.

Diesel engines typically have higher efficiency than gasoline engines due to increased compression ratio and higher energy density of the diesel fuel. A diesel combustion cycle produces particulates that are typically filtered out of the diesel exhaust by a particulate filter (PF) disposed in the exhaust stream. Over time, the PF becomes full and the trapped diesel particulate must be removed. During regeneration, the diesel particulates are burned in the PF.

Conventional regeneration methods inject fuel into the exhaust stream after the main combustion process. The fuel injected after combustion is burned over one or more catalysts placed in the exhaust stream. The heat released on the catalysts during fuel combustion increases the exhaust gas temperature which burns the trapped soot particles in the PF. However, this approach may result in higher temperature excursions than desired, which may be detrimental to exhaust system components, including the PF.

In the US Pat. No. 4,505,107 A is disclosed a particulate filter for a diesel engine, on the front face of which a plurality of heaters in the form of ceramic plates are mounted with printed resistive paths.

The US 4 269 807 A discloses an exhaust catalyst with a ceramic monolith supported by a wire mesh in a metal housing. A circumferential band of intumescent material is disposed in the wire mesh to block exhaust gas flow through the wire mesh as needed.

There is a need to simplify the electrical connection of segmented heatable particulate filters.

SUMMARY

Accordingly, an electrical connection system for a particulate filter is provided. The system comprises: a particulate filter (PF) disposed in an outer shell, the PF being segmented into a plurality of heating zones; an outer mat disposed between the particulate filter and the outer shell; an electrical connector coupled to the outer shell of the PF; and a plurality of printed interconnects extending along the outer surface of the PF from the electrical connector to the plurality of heating zones. The electrical connection system comprises a plurality of pins, wherein a conductive mesh material is embedded and segmented in the outer mat of the particulate filter to conform to the plurality of pins, each segment of the conductive mesh material being surrounded by an insulating material.

Furthermore, an exhaust system is provided which processes exhaust gas generated by an engine. The system includes: a particulate filter (PF) located downstream of the engine that filters out particulates from the exhaust; a grid applied to an upstream outer surface of the PF and which is segmented by non-conductive material into a plurality of zones, each zone comprising a sheet of electrically resistive material; and an electrical connector connected to the particulate filter and supplying energy to the electrical resistance material of each of the plurality of zones. An electrical connection for the particulate filter comprises a plurality of pins, wherein a conductive mesh material is embedded and segmented in the outer mat of the particulate filter to conform to the plurality of pins, each segment of the conductive mesh being surrounded by an insulating material.

Further fields of application will become apparent from the description given here. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for purposes of illustration only and are not intended to limit the scope of the present disclosure in any way.

1 is a functional block diagram of a vehicle that includes a particulate filter.

2 FIG. 10 is a cross-sectional view of a wall-flow monolith particulate filter. FIG.

3 is a cross-sectional view of a portion of the PF of 2 ,

4 is a perspective view of a front surface of the PF.

5 Figure 11 is a side view of the PF including a detailed view of an electrical connection to the PF.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is not intended to limit the invention, its application, or uses. It should be understood that in the drawings, like reference characters designate like or corresponding parts and features. As used herein, the term module refers to an application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group), and memory executing one or more software or firmware programs, a combinatorial logic circuit and / or other suitable components that provide the described functionality.

Now up 1 Turning to an exemplary diesel engine system 10 shown schematically according to the present invention. It can be seen that the diesel engine system 10 is merely exemplary in nature and that the zone-heated particulate filter regeneration system described herein may be embodied in various engine systems that employ a particulate filter. Such engine systems may include, but are not limited to, gasoline direct injection engine systems and homogeneous compression ignition engine (HCCI) engine systems. To facilitate discussion, the disclosure will be discussed in the context of a diesel engine system.

A turbocharged diesel engine system 10 includes a machine 12 which burns an air and fuel mixture to produce a driving torque. Air enters the system by passing through an air filter 14 passes. Air enters through the air filter 14 and gets into a turbocharger 18 sucked. The turbocharger 18 compacts them into the system 10 incoming fresh air. The greater the compression of the air in general, the greater the output of the machine 12 , The compressed air then passes through an air cooler 20 before putting in an intake manifold 22 entry.

The air in the intake manifold 22 is in cylinders 26 distributed. Although four cylinders 26 As can be seen, the systems and methods of the present invention may be embodied in engines having a plurality of cylinders, including, but not limited to, 2, 3, 4, 5, 6, 8, 10 and 12 cylinders. It will also be appreciated that the systems and methods of the present invention may be implemented in a V-cylinder configuration. Fuel gets through fuel injectors 28 in the cylinders 26 injected. Heat from the compressed air ignites the air / fuel mixture. Combustion of the air / fuel mixture produces exhaust. The exhaust gas exits the cylinders 26 in the exhaust system.

The exhaust system includes an exhaust manifold 30 , a Diesel Oxidation Catalyst (DOC) 32 and a particle filter (PF) 34 , Optionally, an EGR valve (not shown) returns some of the exhaust back into the intake manifold 22 , The rest of the exhaust gas gets into the turbocharger 18 passed to power a turbine. The turbine facilitates the compression of the air filter 14 received fresh air. Exhaust gas flows out of the turbocharger 18 through the DOC 32 and the PF 34 , The DOC 32 oxidizes the exhaust gas based on the air / fuel ratio after combustion. The extent of oxidation increases the temperature of the exhaust gas. The PF 34 receives exhaust from the DOC 32 and filters out any soot particles present in the exhaust gas.

A control module 44 controls the machine and the PF regeneration based on various acquired information, in particular, the control module estimates 44 the loading of the PF 34 , When the estimated load reaches a threshold level (eg, 5 grams / liter of particulate matter) and the exhaust gas flow rate is within a desired range, it becomes via a power source 46 a stream to that PF 34 to initiate the regeneration process. The duration of the regeneration process varies based on the amount of particulate matter in the PF 34 , It is expected that the regeneration process can take between 4-6 minutes. However, power is only applied during an initial part of the regeneration process. More specifically, the electrical energy heats the inlet of the PF for a threshold duration (eg, 1-2 minutes). The remainder of the regeneration process is accomplished using the heat generated by combustion of particulate matter at the heated inlet of the PF 34 is available.

With particular reference to 2 is the PF 34 preferably a monolith particulate trap, and includes alternately closed cells / channels 50 and opened cells / channels 52 , A PF mat material 53 surrounds the monolith particle trap. An outer shell 55 surrounds the PF mat 53 , The cells / channels 50 . 52 typically have rectangular cross-sections and extend axially through the part. walls 58 of the PF 34 preferably comprise a porous ceramic honeycomb wall of cordierite material. It will be understood that any honeycomb material is contemplated within the scope of the present invention. Adjacent channels are alternately clogged at each end, as in 56 is shown. This forces the diesel aerosol through the porous substrate walls which act as a mechanical filter. Particulate material is in the closed channels 50 Deposited and exhaust gas passes through the open channels 52 out. soot 59 pour into the PF 34 and are caught in it.

For regeneration purposes is a grid 64 comprising an electrical resistance material secured to the front outer surface, which is referred to as the front surface of the PF 34 referred to as. Current is supplied to the resistive material to generate thermal energy. It will be appreciated that thick film heating technology can be used to grind the grid 64 at the PF 34 to fix. For example, a heating material, such as silver or nichrome, may be applied and then etched or masked onto the front surface of the PF 34 be applied. In various other embodiments, the grid is made of electrical resistance material, such as stainless steel, and is attached to the PF using a ceramic adhesive. It will also be appreciated that the resistance material may be applied in various single or multiple path patterns. Exhaust gas passing through the PF 34 passes, transports thermal energy to the front surface of the PF 34 was generated, a short distance the channels 50 . 52 down. The increased thermal energy ignites particulate matter near the inlet of the PF 34 is available. The heat generated by the combustion of the particles is then passed through the PF to cause combustion of the residual particles in the PF.

With particular reference to 3 In addition, a thermally conductive coating 72 at the inlets 62 of the channels 50 . 52 be upset. The coating 72 may be a short distance the open ends of the closed channels 50 extend down. In various embodiments, the conductive coating extends within one inch (2.54 cm) from the front surface of the PF. The resistance material of the grid 64 contacts the conductive coating 72 , Thermal energy is applied to the conductive coating 72 transferred when electrical energy passes through the resistance material. Heat from the conductive coating 72 ignites particulate matter that is near the inlet of the PF 34 is available.

With reference to 4 can the grid 64 of the PF 34 segmented into multiple zones to reduce the electrical load on the vehicle during regeneration. Each zone can be separately heated by supplying energy to a resistor track located in each zone. It can be seen that the area of the PF 34 can be heated by segmenting the PF into multiple zones according to multiple formats, and therefore is not limited to the current example. As in 4 is shown, the grid of the PF is in three zones 70 - 74 divided up. A single electrical connector 76 can in the PF 34 be added to electrical energy from the power source 46 ( 1 ) to recieve. Printed circuit connections 78 - 84 extend from the electrical connection to the zones 70 - 74 around the outer surface of the PF 34 around. The printed interconnects are conductive traces or traces etched on the non-conductive substrate of the PF. fields 75 receive electrical energy from an electrical outlet (as will be discussed in more detail below) and transmit electrical energy to the printed interconnects 78 - 84 , The printed circuit connections 78 - 84 then transfer the electrical energy to each of the zones 70 - 74 ,

5 FIG. 10 illustrates an electrical connection system to illustrate the zoned heating of the front surface of the PF 34 facilitate via a single point connection. A conductive mesh 100 (eg Grafoil) is in the PF mat 53 embedded. An insulating material 98 (eg, alumina) separates the conductive mesh 100 based on the number of zones in the PF 34 in segments. On the condition of example in 4 in which the front surface of the PF 34 is segmented into three zones, this is the conductive mesh 100 separated into four segments, three with respect to the positive terminal elements of the zones 70 - 74 and one with respect to the negative terminal. The conductive mesh 100 is electrically connected to the printed circuit connections 80 - 82 in connection. A connection 90 includes pens 96 , which press-fit into the port 90 are used. An insulating seal 94 surround the pins 96 , The pencils 96 are on high temperature insulated wires 92 attached to the connector to the vehicle power source 46 from 1 to complete. It will be appreciated that a patch cord configuration may be used to connect to the electrical system of the vehicle.

Those skilled in the art can now appreciate from the foregoing description that the broad teachings of the present disclosure can be embodied in various forms. Therefore, while this disclosure has been described in connection with particular examples thereof, the true scope of the disclosure should not be so limited since other modifications will become apparent to the skilled practitioner upon a study of the drawings, the specification, and the following claims.

Claims (14)

An electrical connection system for a particulate filter, comprising: a particulate filter (PF, 34 ) contained in an outer shell ( 55 ), the PF ( 34 ) into several heating zones ( 70 - 74 ) is segmented; an outer mat ( 53 ) between the particle filter ( 34 ) and the outer shell ( 55 ) is arranged; an electrical connector ( 76 ), with the outer shell ( 55 ) of the PF ( 34 ) is coupled; and several printed circuit connections ( 78 - 84 ) extending along the outer surface of the PF ( 34 ) of the electrical connector ( 76 ) to the several heating zones ( 70 - 74 ), wherein the electrical connection system several pins ( 96 ) and wherein a conductive mesh material ( 100 ) in the outer mat ( 53 ) of the PF ( 34 ) is embedded and segmented to work with the multiple pens ( 96 ), each segment of the conductive mesh ( 100 ) of an insulating material ( 98 ) is surrounded. The system of claim 1, further comprising a plurality of fields ( 75 ) electrically connected to the plurality of printed interconnects ( 78 - 84 ) and wherein each segment of conductive mesh material ( 100 ) one of the several fields ( 75 ) contacted. The system of claim 1, further comprising high temperature insulated conduits ( 92 ) electrically connected to the multiple pins ( 96 ) and from the electrical connector ( 76 ). A system according to claim 3, wherein the high temperature insulated conduits ( 92 ) form a connection cable configuration. The system of claim 1, wherein the conductive mesh material ( 100 ) Grafoil is. System according to claim 1, wherein the insulating material ( 98 ) Is alumina. The system of claim 1, wherein the PF ( 34 ) a grid ( 64 ) made of electrical resistance material, which enters the plurality of heating zones ( 70 - 74 ) is segmented, wherein the grid ( 64 ) on an upstream outer surface of the PF ( 34 ) is applied. Exhaust system, which is controlled by a machine ( 12 processed exhaust gas, comprising: a particulate filter (PF, 34 ), the downstream of the machine ( 12 ) is arranged and filters out the particulate from the exhaust gas; an outer mat ( 53 ) located between an outer surface of the PF ( 34 ) and an outer shell ( 55 ) is arranged; a grid ( 64 ) located on an upstream outer surface of the PF ( 34 ) and that is passed through a non-conductive material into several zones ( 70 - 74 ), each zone comprising a sheet of electrical resistance material; and an electrical connector ( 76 ), which with the particulate filter ( 34 ) and the electrical resistance material of each of the plurality of zones ( 70 - 74 ) Supplying energy, wherein an electrical connection ( 90 ) for the particulate filter ( 34 ) several pens ( 96 ) and wherein a conductive mesh material ( 100 ) in the outer mat ( 53 ) is embedded and segmented to work with the multiple pens ( 96 ), each segment of the conductive mesh ( 100 ) of an insulating material ( 98 ) is surrounded. The system of claim 8, further comprising a plurality of printed circuit connections ( 78 - 84 ) connected by the electrical connector ( 76 ) up to the several zones ( 70 - 74 ) on the outer surface of the PF ( 34 ) are etched. The system of claim 8, wherein the conductive mesh material ( 100 ) Grafoil is. A system according to claim 8, wherein the insulating material ( 98 ) Is alumina. A system according to claim 8, wherein the pins ( 96 ) with interference fit into the electrical connector ( 76 ) are used. The system of claim 12, wherein the electrical connector ( 76 ) an insulating seal ( 94 ) comprising the plurality of pins ( 96 ) surrounds. The system of claim 12, further comprising a high temperature insulated conduit (10). 92 ), which differ from the several pens ( 96 ).

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